package demo6;

/**
 * 最长回文子串
 */
public class test2 {
    public String longestPalindrome(String s) {
        // 创建dp表
        int n = s.length();
        boolean[][] dp = new boolean[n][n];
        // 初始化

        int len = 1;
        int begin = 0;
        for(int i = n-1; i >= 0; i--){
            for(int j = i; j < n; j++){
                if(s.charAt(i) == s.charAt(j)){
                    dp[i][j] = i+1<j ? dp[i+1][j-1] : true;
                }
                if(dp[i][j] && j-i+1 > len){
                    len = j-i+1;
                    begin = i;
                }
            }
        }
        return s.substring(begin, begin+len);
    }
}
